Precoding processing method and user equipment

ABSTRACT

A precoding processing method and user equipment are disclosed. The precoding processing method includes: selecting a codebook vector for performing precoding processing for data among a codebook set of N t  antennas, where the codebook set includes a first codebook vector 
                   [         A           B         ]           
of a uniform linear array and a second codebook vector
 
                   [         A             -   B           ]           
generated according to the first codebook vector, where A is a (N t /2)×1 vector composed of a first half of elements of the first codebook vector, B is a (N t /2)×1 vector composed of a last half of elements of the first codebook vector, and N t  is a positive even number; and sending an index number of the codebook vector to a base station, whereupon the base station uses the codebook vector corresponding to the index number to perform precoding processing for the data to be transmitted by the antennas. Embodiments of the present invention make the codebook set compatible with two types of antenna configuration modes.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of International Patent ApplicationNo. PCT/CN2011/073501, filed on Apr. 29, 2011, which claims priority toChinese Patent Application No. 201010168659.X, filed on May 4, 2010,both of which are hereby incorporated by reference in their entireties.

FIELD OF THE INVENTION

The present invention relates to the communication field, and inparticular, to a precoding processing method and user equipment.

BACKGROUND OF THE INVENTION

Long Term Evolution-Advanced (Long Term Evolution-Advanced, LTE-A) isfollow-up evolution of the LTE technology. In the LTE-A, a base stationmay use 8 antennas to transmit data. The 8 antennas may be configured intwo modes. One mode is uniform linear array (Uniform Linear Array, ULAfor short) antennas, and the other mode is dual-polarized antennas. FIG.1 is a schematic structural diagram of an ULA antenna, and FIG. 2 is aschematic structural diagram of a dual-polarized antenna. As shown inFIG. 1 and FIG. 2, in the ULA antennas, 8 antennas have the samepolarization direction, and the spacing between the 8 antennas is 0.5λ.In the dual-polarized antennas, the polarization direction of antennas1-4 is different from the polarization direction of antennas 5-8.

In the prior art, the codebook structure of the ULA antenna is designedfor the ULA antenna, and the codebook structure of the dual-polarizedantenna is designed for the dual-polarized antenna, and the codebookstructure is not compatible between the two types of antennas, whichleads to resource redundancy.

SUMMARY OF THE INVENTION

Embodiments of the present invention provide a precoding processingmethod and user equipment to make the codebook set be compatible withtwo types of antenna configuration modes and reduce resource redundancy.

A precoding processing method provided in an embodiment of the presentinvention includes:

selecting a codebook vector for performing precoding processing for dataamong a codebook set of N_(t) antennas, where the codebook set includesa first codebook vector

$\quad\begin{bmatrix}A \\B\end{bmatrix}$of a uniform linear array and a second codebook vector

$\quad\begin{bmatrix}A \\{- B}\end{bmatrix}$generated according to the first codebook vector, wherein, A is a(N_(t)/2)×1 vector composed of a first half of elements of the firstcodebook vector, B is a (N_(t)/2)×1 vector composed of a last half ofelements of the first codebook vector, and N_(t) is a positive evennumber; and

sending an index number of the codebook vector to a base station,whereupon the base station uses the codebook vector corresponding to theindex number to perform precoding processing for the data to betransmitted by the antennas.

A user equipment provided in an embodiment of the present inventionincludes:

a codebook selecting module, configured to select a codebook vector forperforming precoding processing for data among a codebook set of N_(t)antennas, where the codebook set includes a first codebook vector

$\quad\begin{bmatrix}A \\B\end{bmatrix}$of a uniform linear array and a second codebook vector

$\quad\begin{bmatrix}A \\{- B}\end{bmatrix}$generated according to the first codebook vector, and A is a (N_(t)/2)×1vector composed of a first half of elements of the first codebookvector, B is a (N_(t)/2)×1 vector composed of a last half of elements ofthe first codebook vector, and N is a positive even number; and

a sending module, configured to send an index number of the codebookvector selected by the codebook selecting module to a base station,whereupon the base station uses the codebook vector corresponding to theindex number to perform precoding processing for the data to betransmitted by the antennas.

In the embodiments of the present invention, the user equipment mayselect a codebook vector in a codebook set that is compatible with boththe ULA configuration mode and the dual polarization configuration mode,and send the index number corresponding to the codebook vector to thebase station, and therefore, the base station can use the codebookvector to perform precoding processing for the data to be sent. Throughthe codebook set in the embodiments of the present invention, thelargest possible number of codebooks are applicable to both the ULAantenna and the dual-polarized antennas, which provides highcompatibility and avoids resource redundancy.

BRIEF DESCRIPTION OF THE DRAWINGS

To illustrate the technical solutions according to the embodiments ofthe present invention or in the prior art more clearly, accompanyingdrawings required for describing the embodiments or the prior art areintroduced briefly below. Apparently, the accompanying drawings in thefollowing description are merely some embodiments of the presentinvention, and persons of ordinary skill in the art may further obtainother drawings according to the accompanying drawings without creativeefforts.

FIG. 1 is a schematic structural diagram of an ULA antenna;

FIG. 2 is a schematic structural diagram of a dual-polarized antenna;

FIG. 3 is a flowchart of a precoding processing method according to anembodiment of the present invention;

FIG. 4 is a flowchart of a precoding processing method according toanother embodiment of the present invention;

FIG. 5 is another schematic structural diagram of a ULA antenna appliedto the present invention;

FIG. 6 is a schematic structural diagram of a dual-polarized antennaapplied to the present invention;

FIG. 7 is a schematic structural diagram of user equipment according toan embodiment of the present invention;

FIG. 8 is a schematic structural diagram of user equipment according toanother embodiment of the present invention; and

FIG. 9 is a schematic structural diagram of user equipment according toanother embodiment of the present invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS

To make the objectives, technical solutions, and advantages of theembodiments of the present invention clearer, the technical solutions ofthe embodiments in the present invention are hereinafter describedthoroughly with reference to the accompanying drawings. Evidently, thedescribed embodiments are merely some embodiments rather than allembodiments of the present invention. All other embodiments, which canbe derived by persons of ordinary skill in the art from the embodimentsof the present invention without any creative effort, shall fall withinthe protection scope of the present invention.

FIG. 3 is a flowchart of a precoding processing method according to anembodiment of the present invention. As shown in FIG. 3, the method inthis embodiment may include the following steps:

Step 301: Select a codebook vector for performing precoding processingfor data among a codebook set of N_(t) antennas.

In this embodiment, the codebook set includes a first codebook vector

$\quad\begin{bmatrix}A \\B\end{bmatrix}$of a ULA antenna and a second codebook vector

$\quad\begin{bmatrix}A \\{- B}\end{bmatrix}$generated according to the first codebook vector, where A is a(N_(t)/2)×1 vector composed of a first half of elements of the firstcodebook vector, and B is a (N_(t)/2)×1 vector composed of a last halfof elements of the first codebook vector.

Specifically, the user equipment (User Equipment, UE for short) mayselect a codebook vector among the codebook set, where the codebook setmay be used by the base station to perform precoding processing for thedata to be transmitted. Specifically, the UE may select a codebookvector among the codebook set of N_(t) antennas according to theconfiguration mode of the antenna. In this embodiment, the codebook setincludes the first codebook vector

$\quad\begin{bmatrix}A \\B\end{bmatrix}$and the second codebook vector.

$\quad{\begin{bmatrix}A \\{- B}\end{bmatrix}.}$The first codebook vector

$\quad\begin{bmatrix}A \\B\end{bmatrix}$is a codebook vector designed according to the ULA configuration mode,and the second codebook vector is generated according to the firstcodebook vector. For example, the codebook set may include 16 codebookvectors, 8 of which are the first codebook vectors

$\quad{\begin{bmatrix}A \\B\end{bmatrix}.}$Every first codebook vector

$\quad\begin{bmatrix}A \\B\end{bmatrix}$corresponds to a second codebook vector

$\begin{bmatrix}A \\{- B}\end{bmatrix}.$Therefore, the 8 first codebook vectors

$\quad\begin{bmatrix}A \\B\end{bmatrix}$correspond to 8 second codebook vectors

$\begin{bmatrix}A \\{- B}\end{bmatrix}.$

For the first codebook vector

$\begin{bmatrix}A \\B\end{bmatrix},$the codebook design may draw upon an existing discrete Fouriertransformation (Discrete Fourier Transform, DFT for short) codebookstructure. The calculation formula is as follows:

$\begin{matrix}{e_{m}^{(g)} = {\frac{1}{\sqrt{M}}\left\lbrack {w_{0\; m}^{(g)}\mspace{14mu}\ldots\mspace{14mu} w_{{({M - 1})}m}^{(g)}} \right\rbrack}^{T}} & (1) \\{w_{nm}^{(g)} = {\exp\left\{ {j\frac{2\pi\; n}{M}\left( {m + \frac{g}{G}} \right)} \right\}}} & \;\end{matrix}$

In the formula above, M is the number of dimensions of DFT, m=0, 1 . . .M−1, n=0, 1 . . . M−1. For example, in the DFT corresponding to 8antennas, M=8; in the DFT corresponding to 4 antennas, M=4. G is thenumber of groups of DFT, g=0, 1, . . . , G−1. e_(m) ^((g)) is aprecoding vector in the codebook set, and w_(nm) ^((g)) representsvarious elements in e_(m) ^((g)). For example, if N_(t)=4, namely, if 4transmitting antennas are introduced in the base station, a4-dimensional DFT structure may be used to obtain four 4×1 precodingvectors. To generate a codebook set that includes 16 codebooks, G may beset to 4 so that 16 codebooks can be obtained.

Therefore, for the antennas that employ the ULA configuration mode, theUE may select any codebook vector among the codebook set, and thecodebook set in this embodiment is compatible with the ULA configurationmode.

Further, the codebook set in this embodiment is compatible with the dualpolarization configuration mode. Specifically, taking the structure ofthe dual-polarized antenna shown in FIG. 2 as an example, the totalnumber of the dual-polarized antennas is 8, namely, N_(t)=8. Thepolarization mode of antennas 1-4 is different from the polarizationmode of antennas 5-8. Because the 4 antennas of the same polarizationmode are a uniform linear array, it is assumed that each group ofdual-polarized antennas have the same directivity information, but arandom phase relationship exists between two polarized antenna groups.Therefore, the codebook set of the dual-polarized antennas may beexpressed as:

$\begin{matrix}{\begin{bmatrix}A \\{\alpha\; A}\end{bmatrix},{\alpha \in \left( {1,1,j,{- j}} \right)}} & (2)\end{matrix}$

In the expression above, A is a 4×1 vector selected in a 4-dimensionalDFT codebook structure. α serves to adjust the phase relationship of twogroups of polarized antennas.

Experiments prove that the codebook set created according to thisembodiment can include the largest possible number of codebooksapplicable to both the ULA antenna and the dual-polarized antennas.

Step 302: Send an index number of the codebook vector to a base station,whereupon the base station uses the codebook vector corresponding to theindex number to perform precoding processing for the data to betransmitted by the antennas.

After selecting the codebook vector, the UE may send the index numbercorresponding to the codebook vector to the base station, whereupon thebase station uses the codebook vector to perform precoding processingfor the data to be transmitted by the antennas. It should be noted thatthis embodiment does not restrict the specific mode of using thecodebook vector to perform precoding processing for the data to betransmitted, and those skilled in the art can select the mode asrequired.

In this embodiment, the user equipment may select a codebook vector in acodebook set that is compatible with both the ULA configuration mode andthe dual polarization configuration mode, and send the index numbercorresponding to the codebook vector to the base station, and therefore,the base station can use the codebook vector to perform precodingprocessing for the data to be sent. Through the codebook set in theembodiments of the present invention, the largest possible number ofcodebooks are applicable to both the ULA antenna and the dual-polarizedantennas, which provides high compatibility and avoids resourceredundancy.

FIG. 4 is a flowchart of a precoding processing method according toanother embodiment of the present invention. As shown in FIG. 4, themethod in this embodiment includes the following steps:

Step 401: Obtain an antenna configuration mode. For a dual polarizationconfiguration mode, proceed to step 402; for a ULA configuration mode,proceed to step 403.

Step 402: Select a codebook vector in the first codebook vector and thesecond codebook vector of the codebook set, and proceed to step 404.

Step 403: Select a codebook vector in the first codebook vectors of thecodebook set, and proceed to step 404.

Step 404: Send an index number of the codebook vector to a base station,whereupon the base station uses the codebook vector corresponding to theindex number to perform precoding processing for the data to betransmitted by the antennas.

Specifically, on the basis of the embodiment shown in FIG. 3, thisembodiment further defines the codebook set. More specifically, N_(t)=8,the spacing between the 8 antennas is a small spacing, and the codebookset in this embodiment includes K codebooks; wherein the 8×1 codebookvector

$\quad\begin{bmatrix}A \\B\end{bmatrix}$corresponding to K/2 codebooks in the K codebooks respectively isobtained by using an 8-dimensional discrete Fourier transformationcodebook structure, and the number of the discrete Fouriertransformation groups is K/(2Nt); the codebook vector of the other K/2codebooks in the K codebooks is

$\begin{bmatrix}A \\{- B}\end{bmatrix},$where A is a vector composed of the first 4 elements in the 8×1 codebookvector, and B is a vector composed of the last 4 elements in the 8×1codebook vector.

Specifically, the spacing between highly dependent antennas is small,for example, antennas shown in FIG. 1 and FIG. 2. This embodiment maydesign 5-bit 8-antenna codebooks whose rank is 1, namely, the number ofcodebooks is K=32. First, sixteen 8×1 codebook vectors

$\quad\begin{bmatrix}A \\B\end{bmatrix}$may be obtained according to formula (1). The 16 codebook vectors are apart of the 32 codebooks of 8 antennas. For each of the 16 codebookvectors, the first 4 elements are expressed as A, and the last 4elements are expressed as B, and therefore, the 16 codebook vectors maybe expressed as

$\begin{bmatrix}A \\B\end{bmatrix},$and the other 16 codebook vectors are generated as

$\begin{bmatrix}A \\{- B}\end{bmatrix}.$Analysis shows that the generated 32 codebooks correspond to the8-antenna dual-polarized codebooks. Table 1 shows a mapping relationshipbetween the generated 32 codebooks and the generated 8-antennadual-polarized codebooks.

TABLE 1

The codebook structure AAjAA of the dual-polarized antenna shown informula (2) includes:

$\begin{bmatrix}A \\A\end{bmatrix},\begin{bmatrix}A \\{- A}\end{bmatrix},\begin{bmatrix}A \\{j\; A}\end{bmatrix},\begin{bmatrix}A \\{{- j}\; A}\end{bmatrix}$

The AA structure shown in Table 1 is:

$\begin{bmatrix}A \\A\end{bmatrix},\begin{bmatrix}A \\{- A}\end{bmatrix}$

The AjA structure shown in Table 1 is:

$\begin{bmatrix}A \\{j\; A}\end{bmatrix},\begin{bmatrix}A \\{{- j}\; A}\end{bmatrix}$

The AB structure shown in Table 1 is:

$\begin{bmatrix}A \\B\end{bmatrix},\begin{bmatrix}A \\{- B}\end{bmatrix}$

In Table 1, the 16 codebook vectors generated by g=0 in the 8-antenna ABstructure (G=2, M=8) are the same as the 16 codebook vectors generatedby g=0 and g=2 in the 4-antenna AA structure (G=4, M=4); and the 16codebook vectors generated by g=1 in the 8-antenna AB structure (G=2,M=8) are the same as the 16 codebook vectors generated by g=1 and g=3 inthe 4-antenna AjA structure (G=4, M=4).

Specifically, the 5-bit codebooks shown in Table 1 make up a codebookset that includes 2⁵=32 codebook vectors.

In the AAjAA structure, M=4, and g=0, 1, 2, 3.

In the AB structure, M=8, and g=0, 1.

(i) Compare the codebook vectors of (M=4, G=4, g=0 or g=2) in the AAstructure with the codebook vectors of (M=8, G=2, g=0) in the ABstructure.

If M=8 and g=0 in the AB structure, each element in the codebook vectoris:

${\exp\left\{ {j\frac{2\pi\; n}{8}(m)} \right\}};$

If m=0, 2, 4, 6, let m=2k, (k is 0, 1, 2, 3), and each element of theupper half part A (n=0, 1, 2, 3) of the AB structure is:

${{\exp\left\{ {j\frac{2\pi\; n}{8}\left( {2\; k} \right)} \right\}} = {\exp\left\{ {j\frac{2\pi\;{nk}}{4}} \right\}}};$

If M=4 and g=0 in the AA structure, each element in the codebook vectoris:

${\exp\left\{ {j\frac{2\pi\; n}{M}\left( {m + \frac{0}{G}} \right)} \right\}} = {\exp{\left\{ {j\frac{2\pi\; n}{4}(m)} \right\}.}}$

In this case, the 4 elements of the upper half part A of the ABstructure are the same as the 4 elements of (M=4, g=0) of the AAstructure.

The lower half part B (n=4, 5, 6, 7) of the codebook vector may beexpressed as:

${\exp\left\{ {j\frac{2{\pi\left( {n + 4} \right)}}{8}\left( {2\; k} \right)} \right\}} = {{\exp\left\{ {{j\frac{2\pi\;{nk}}{4}} + {2\; k\;\pi}} \right\}} = {\exp{\left\{ {j\frac{2\pi\;{nk}}{4}} \right\}.}}}$

Therefore, herein the lower half part B of the codebook vector=the upperhalf part A.

Therefore, in this case, the AB structure and the AA structure have:

$\begin{bmatrix}{A = A} \\{B = A}\end{bmatrix},{\begin{bmatrix}{A = A} \\{{- B} = {- A}}\end{bmatrix}.}$

When m is an odd number, namely, m=2k+1,

each element in the upper half part A (n=0, 1, 2, 3) of the AB structureis:

${\exp\left\{ {j\frac{2\pi\; n}{8}\left( {{2\; k} + 1} \right)} \right\}} = {\exp{\left\{ {j\left( {\frac{2\pi\;{nk}}{4} + \frac{2\pi\; n}{8}} \right)} \right\}.}}$

If M=4, G=4 and g=2 in the 4-antenna AA structure,

${\exp\left\{ {j\frac{2\pi\; n}{4}\left( {m + \frac{2}{4}} \right)} \right\}} = {\exp{\left\{ {j\left( {\frac{2\pi\;{nm}}{4} + \frac{2\pi\; n}{8}} \right)} \right\}.}}$

Therefore, the vectors of the 4-antenna AA structure with (M=4, G=4,g=2) are the same as the upper half part A of the codebook vectors ofthe AB structure.

The lower half part B (n=4, 5, 6, 7) of the codebook vector may beexpressed as:

${\exp\left\{ {j\frac{2{\pi\left( {n + 4} \right)}}{8}\left( {{2\; k} + 1} \right)} \right\}} = {{\exp\left\{ {{j\frac{2\pi\;{nk}}{4}} + {2\; k\;\pi} + \frac{2\pi\; n}{8} + \pi} \right\}} = {{- \exp}{\left\{ {{j\frac{2\pi\;{nk}}{4}} + \frac{2\pi\; n}{9}} \right\}.}}}$

In this case, B=−A.

Therefore, in this case, the mapping relationship between the ABstructure and the AA structure is:

$\begin{bmatrix}{A = A} \\{B = {- A}}\end{bmatrix},{\begin{bmatrix}{A = A} \\{{- B} = A}\end{bmatrix}.}$

(ii) Compare the codebook vectors of (M=4, g=1 or g=3 (G=4)) in the AjAstructure with the codebook vectors of (M=8, g=1) in the AB structure.

If M=8 and g=1 in the AB structure, each element in the codebook vectoris:

${\exp\left\{ {j\frac{2\pi\; n}{8}\left( {m + \frac{1}{2}} \right)} \right\}};$

If m=0, 2, 4, 6, let m=2k, (k is 0, 1, 2, 3), and each element of theupper half part A (n=0, 1, 2, 3) of the AB structure is:

${\exp\left\{ {j\frac{2\pi\; n}{8}\left( {{2\; k} + \frac{1}{2}} \right)} \right\}} = {\exp{\left\{ {j\left( {\frac{2\pi\;{nk}}{4} + \frac{2\pi\; n}{16}} \right)} \right\}.}}$

If G=4, M=4 and g=1 in the AA structure, each element in the codebookvector is:

${\exp\left\{ {j\frac{2\pi\; n}{4}\left( {m + \frac{1}{4}} \right)} \right\}} = {\exp{\left\{ {j\left( {\frac{2\pi\;{nm}}{4} + \frac{2\pi\; n}{16}} \right)} \right\}.}}$

In this case, the 4 elements of the upper half part A of the codebookvector in the AB structure are the same as the 4 elements of (M=4, g=0)in the AA structure.

The lower half part B (n=4, 5, 6, 7) of the codebook vector may beexpressed as:

${\exp\left\{ {j\frac{2{\pi\left( {n + 4} \right)}}{8}\left( {{2\; k} + \frac{1}{2}} \right)} \right\}} = {{\exp\left\{ {j\left( {\frac{2\pi\;{nk}}{4} + \frac{2\pi\; n}{16} + \frac{\pi}{2}} \right)} \right\}} = {j \times \exp{\left\{ {j\left( {\frac{2\pi\;{nk}}{4} + \frac{2\pi\; n}{16}} \right)} \right\}.}}}$Therefore, the lower half part of the codebook vector is B=jA.

Therefore, in this case, the mapping relationship between the ABstructure and the AjA structure is:

$\begin{bmatrix}{A = A} \\{B = {j\; A}}\end{bmatrix},{\begin{bmatrix}{A = A} \\{{- B} = {{- j}\; A}}\end{bmatrix}.}$

When m is an odd number, namely, m=2k+1,

each element in the upper half part A (n=0, 1, 2, 3) of the AB structureis:

${\exp\left\{ {j\frac{2\pi\; n}{8}\left( {{2\; k} + 1 + \frac{1}{2}} \right)} \right\}} = {\exp{\left\{ {j\left( {\frac{2\pi\;{nk}}{4} + \frac{2{\pi 3}\; n}{16}} \right)} \right\}.}}$

If M=4, G=4 and g=3 in the 4-antenna AjA structure,

${\exp\left\{ {j\frac{2\pi\; n}{4}\left( {m + \frac{3}{4}} \right)} \right\}} = {\exp{\left\{ {j\left( {\frac{2\pi\; n\; m}{4} + \frac{2\pi\; 3n}{16}} \right)} \right\}.}}$

Therefore, the 4 elements of the upper half part A of the codebookvector in the AB structure are the same as the 4 elements of (M=4, g=0)of the AjA structure.

The lower half part B (n=4, 5, 6, 7) of the codebook vector may beexpressed as:

$\begin{matrix}{{\exp\left\{ {j\frac{2{\pi\left( {n + 4} \right)}}{8}\left( {{2k} + 1 + \frac{1}{2}} \right)} \right\}} = {\exp\left\{ {j\left( {\frac{2\pi\; n\; k}{4} + \frac{2\pi\; 3n}{16} + \pi + \frac{\pi}{2}} \right)} \right\}}} \\{= {{- {jexp}}{\left\{ {j\left( {\frac{2\pi\; n\; k}{4} + \frac{2\pi\; 3n}{16}} \right)} \right\}.}}}\end{matrix}$

In this case, the lower half part of the codebook vector of the ABstructure is B=−jA.

Therefore, in this case, the mapping relationship between the ABstructure and the AA structure is:

$\begin{bmatrix}{A = A} \\{B = {{- j}\; A}}\end{bmatrix},{\begin{bmatrix}{A = A} \\{{- B} = {j\; A}}\end{bmatrix}.}$

Therefore, in this embodiment, the codebook vectors of the AB structureare a result of extracting 16 codebook vectors from (g=0, g=2) of the AAstructure and extracting 16 codebook vectors from (g=1, g=3) of the AjAstructure. In the codebook set of 32 codebook vectors generatedaccording to such a structure, all codebook vectors are applicable todual polarization configuration. Moreover, the codebook set is obtainedbased on the 8-antenna DFT codebook structure. Therefore, the 16codebook vectors of the codebook set are applicable to ULAconfiguration. Therefore, the codebook set in this embodiment iscompatible with both the antennas configured in a ULA mode and theantennas configured in a dual polarization mode.

Therefore, in this embodiment, if the UE knows that the antennas areconfigured in a ULA mode, the UE may choose to obtain codebook vectorsfrom a first codebook set, where the first codebook set is composed of16 codebook vectors that are obtained based on an 8-antenna DFT codebookstructure, whereupon the base station can use the codebook vectors toperform precoding processing; if the UE knows that the antennas aredual-polarized antennas, the UE may select codebook vectors among all 32codebook vectors, namely, among the first codebook set and the secondcodebook set, whereupon the base station can use the codebook vectors toperform precoding processing.

It should be noted that in this embodiment, the UE does not necessarilyknow the configuration mode of the antennas, but rather makes blindselection in the codebook set of this embodiment to obtain the firstcodebook.

In this embodiment, the UE may select codebook vectors among thecodebook set compatible with both the ULA configuration mode and thedual polarization configuration mode according to the configuration modeof the antenna. If the antenna is configured in a ULA mode, the UE mayselect codebook vectors among the first codebook set of the codebookset; if the antenna is configured in a dual polarization mode, the UEmay select codebook vectors among the second codebook set of thecodebook set. In this way, the index numbers corresponding to thecodebook vectors may be sent to the base station so that the basestation can use the codebook vectors corresponding to the index numbersto perform procoding processing for the data to be sent. Through thecodebook set in the embodiments of the present invention, the largestpossible number of codebook vectors are applicable to both the ULAantenna and the dual-polarized antennas, which provides highcompatibility and avoids resource redundancy.

FIG. 5 is another schematic structural diagram of an ULA antenna, andFIG. 6 is another schematic structural diagram of a dual-polarizedantenna. As shown in FIG. 5 and FIG. 6, the ULA antennas and thedual-polarized antennas are divided into two groups, with antennas 1-4forming one group and antennas 5-8 forming another group. The spacingbetween the four antennas in antennas 1-4 or antennas 5-8 is a smallspacing such as 0.5λ; and the spacing between antennas 1-4 and antennas5-8 is a large spacing such as 10λ. In such an antenna layout, thetransmitting directions of the two groups of antennas are different, orin other words, the 4-dimensional DFT vectors they used are different.For example, the DFT vector selected by antennas 1-4 is A, but the DFTvector selected by antennas 5-8 is B, and a constant is still requiredbetween the two groups of antennas to indicate the directionrelationship between the two groups of antennas.

Therefore, in the precoding processing method according to anotherembodiment of the present invention, the codebook set may include Kcodebooks, and the K codebooks include the first codebook vector

$\quad\begin{bmatrix}A \\B\end{bmatrix}$and the second codebook vector

$\begin{bmatrix}A \\{- B}\end{bmatrix},$where A is a 4×1 vector obtained by using a 4-dimensional DFT codebookstructure and corresponding to one group of antennas, and B is a 4×1vector obtained by using a 4-dimensional DFT codebook structure andcorresponding to another group of antennas. In this embodiment, thecodebook may be expressed as

$\begin{bmatrix}A \\{\alpha\; B}\end{bmatrix},$αε(1, −1).

This embodiment does not need to differentiate the antenna configurationmodes, and the UE can select codebook vectors in the codebook set nomatter whether the antenna configuration mode is the ULA configurationmode shown in FIG. 5 or the dual polarization configuration mode shownin FIG. 6, and therefore, the base station can use the codebook vectorsto perform precoding processing for the data to be sent. Therefore, thecodebook set in this embodiment is compatible with both ULA antennas anddual-polarized antennas. The compatibility is high, and the resourceredundancy is avoided.

FIG. 7 is a schematic structural diagram of user equipment according toan embodiment of the present invention. As shown in FIG. 7, the UE inthis embodiment may include a codebook selecting module 11 and a sendingmodule 12. The codebook selecting module 11 is configured to select acodebook vector for performing precoding processing for data among acodebook set of N_(t) antennas, where the codebook set includes a firstcodebook vector

$\quad\begin{bmatrix}A \\B\end{bmatrix}$of a uniform linear array and a second codebook vector

$\quad\begin{bmatrix}A \\{- B}\end{bmatrix}$generated according to the first codebook vector, and A is a (N_(t)/2)×1vector composed of a first half of elements of the first codebookvector, B is a (N_(t)/2)×1 vector composed of a last half of elements ofthe first codebook vector, and (N_(t) is a positive even number, forexample, 2 multiplied by itself a positive number of times; and thesending module 12 is configured to send an index number of the codebookvector selected by the codebook selecting module 11 to a base station,whereupon the base station uses the codebook vector corresponding to theindex number to perform precoding processing for the data to betransmitted by the antennas.

The UE in this embodiment may be used to implement the method in themethod embodiment shown in FIG. 3, and the implementation principles aresimilar and will not be repeated here any further.

In this embodiment, the user equipment may select a codebook vector in acodebook set that is compatible with both the ULA configuration mode andthe dual polarization configuration mode, and send the index numbercorresponding to the codebook vector to the base station, and therefore,the base station can use the codebook vector to perform precodingprocessing for the data to be sent. Through the codebook set in theembodiments of the present invention, the largest possible number ofcodebooks are applicable to both the ULA antenna and the dual-polarizedantennas, which provides high compatibility and avoids resourceredundancy.

FIG. 8 is a schematic structural diagram of user equipment according toanother embodiment of the present invention. As shown in FIG. 8, on thebasis of the user equipment shown in FIG. 7, the user equipment in thisembodiment further includes a first storage module 13. The first storagemodule 13 is configured to store the codebook set, where N_(t)=8, thespacing between the 8 antennas is a small spacing, and the codebook setincludes K codebooks; the 8×1 codebook vector

$\quad\begin{bmatrix}A \\B\end{bmatrix}$corresponding to K/2 codebooks in the K codebooks respectively isobtained by using an 8-dimensional discrete Fourier transformationcodebook structure, and the number of the discrete Fouriertransformation groups is K/(2Nt); the codebook vector of the other K/2codebooks in the K codebooks is

$\begin{bmatrix}A \\{- B}\end{bmatrix},$where A is a vector composed of the first 4 elements in the 8×1 codebookvector, and B is a vector composed of the last 4 elements in the 8×1codebook vector. Correspondingly, the codebook selecting module 11 isspecifically configured to select a codebook vector for performingprecoding processing for data among the codebook set stored by the firststorage module. In this embodiment, the codebook selecting module 11 mayinclude a judging unit 111 and a selecting unit 112. The judging unit111 is configured to judge whether the configuration mode of the antennais a dual polarization configuration mode or a uniform linear arrayconfiguration mode. The selecting unit 112 is configured to: select thecodebook vector in the first codebook vector and the second codebookvector of the codebook set if the judging unit 111 determines that theconfiguration mode of the antenna is a dual polarization configurationmode; and select the codebook vector in the first codebook vector of thecodebook set if the judging unit 111 determines that the configurationmode of the antenna is a uniform linear array configuration mode.

The UE in this embodiment may be used to implement the method in themethod embodiment shown in FIG. 4, and the implementation principles aresimilar and will not be repeated here any further.

In this embodiment, the user equipment may select codebook vectors amongthe codebook set compatible with both the ULA configuration mode and thedual polarization configuration mode according to the configuration modeof the antenna. If the antenna is configured in a ULA mode, the userequipment may select codebook vectors among the first codebook set; ifthe antenna is configured in a dual polarization mode, the userequipment may select codebook vectors among the second codebook set. Inthis way, the index numbers corresponding to the codebook vectors may besent to the base station so that the base station can use the codebookvectors corresponding to the index numbers to perform procodingprocessing for the data to be sent. Through the codebook set in theembodiments of the present invention, the largest possible number ofcodebook vectors are applicable to both the ULA antenna and thedual-polarized antennas, which provides high compatibility and avoidsresource redundancy.

FIG. 9 is a schematic structural diagram of user equipment according toanother embodiment of the present invention. As shown in FIG. 9, on thebasis of the user equipment shown in FIG. 7, the user equipment in thisembodiment further includes a second storage module 14. The secondstorage module 14 is configured to store the codebook set, whereN_(t)=8, the 8 antennas are divided into two groups, the spacing between4 antennas in each group is a small spacing, and the spacing between thetwo groups of antennas is a large spacing; the codebook set includes Kcodebooks, and the K codebooks include a first codebook vector

$\quad\begin{bmatrix}A \\B\end{bmatrix}$and a second codebook vector

$\begin{bmatrix}A \\{- B}\end{bmatrix},$where A is a 4×1 vector obtained by using a 4-dimensional discreteFourier transformation codebook structure and corresponding to one groupof antennas, and B is a 4×1 vector obtained by using a 4-dimensionaldiscrete Fourier transformation codebook structure and corresponding tothe other group of antennas. Correspondingly, the codebook selectingmodule 11 is specifically configured to select a codebook vector forperforming precoding processing for data among the codebook set storedby the second storage module 14.

The user equipment in this embodiment is applicable to the antennalayout shown in FIG. 5 or FIG. 6. In this embodiment, the UE need notdifferentiate the antenna configuration modes, the UE can selectcodebook vectors in the codebook set no matter whether the antennaconfiguration mode is the ULA configuration mode shown in FIG. 5 or thedual polarization configuration mode shown in FIG. 6, and therefore, thebase station can use the codebook vectors to perform precodingprocessing for the data to be sent. Therefore, in this embodiment, thecodebook set stored in the user equipment is highly compatible, therebyavoiding resource redundancy.

Correspondingly, in the codebook set of an embodiment of the presentinvention, the codebook set includes a first codebook vector

$\quad\begin{bmatrix}A \\B\end{bmatrix}$and a second codebook vector

$\begin{bmatrix}A \\{- B}\end{bmatrix},$where the first codebook vector is a codebook vector of a uniform lineararray, A is a (N_(t)/2)×1 vector composed of a first half of elements ofthe first codebook vector, B is a (N_(t)/2)×1 vector composed of a lasthalf of elements of the first codebook vector, and N_(t) is the numberof antennas and is a positive even number. The codebook set is thecodebook set applied in the method embodiment shown in FIG. 3. Thefunctions and purposes of the codebook set are detailed in the methodembodiment shown in FIG. 3 and will not be repeated here any further.

Further, to adapt to the antenna layout shown in FIG. 1 and FIG. 2, inwhich N_(t)=8 and the spacing between the 8 antennas is a small spacing,the codebook set includes K codebooks; wherein, the 8×1 codebook vector

$\quad\begin{bmatrix}A \\B\end{bmatrix}$corresponding to K/2 codebooks in the K codebooks respectively isobtained by using an 8-dimensional discrete Fourier transformationcodebook structure, and the number of the discrete Fouriertransformation groups is K/(2Nt); the codebook vector of the other K/2codebooks in the K codebooks is

$\begin{bmatrix}A \\{- B}\end{bmatrix},$where A is a vector composed of the first 4 elements in the 8×1 codebookvector, and B is a vector composed of the last 4 elements in the 8×1codebook vector. The codebook set is the codebook set applied in themethod embodiment shown in FIG. 4. The functions and purposes of thecodebook set are detailed in the method embodiment shown in FIG. 4 andwill not be repeated here any further.

Further, to adapt to the antenna layout shown in FIG. 5 and FIG. 6,N_(t)=8 and the 8 antennas are divided into two groups, the spacingbetween 4 antennas in each group is a small spacing, and the spacingbetween the two groups of antennas is a large spacing; the codebook setincludes K codebooks, and the K codebooks include a first codebookvector

$\quad\begin{bmatrix}A \\B\end{bmatrix}$and a second codebook vector

$\begin{bmatrix}A \\{- B}\end{bmatrix},$where A is a 4×1 vector obtained by using a 4-dimensional discreteFourier transformation codebook structure and corresponding to one groupof antennas, and B is a 4×1 vector obtained by using a 4-dimensionaldiscrete Fourier transformation codebook structure and corresponding tothe other group of antennas.

The codebook set in this embodiment is applicable to the antenna layoutshown in FIG. 5 or FIG. 6. In this embodiment, the UE need notdifferentiate the antenna configuration modes, the UE can selectcodebook vectors in the codebook set no matter whether the antennaconfiguration mode is the ULA configuration mode shown in FIG. 5 or thedual polarization configuration mode shown in FIG. 6, and therefore, thebase station can use the codebook vectors to perform precodingprocessing for the data to be sent. Therefore, in this embodiment, thecodebook set stored in the user equipment is highly compatible, therebyavoiding resource redundancy.

Persons of ordinary skill in the art should understand that all or partof the steps of the method specified in any embodiment of the presentinvention may be implemented by a program instructing relevant hardware.The program may be stored in a computer readable storage medium. Whenthe program runs, the program executes the steps of the method specifiedin any embodiment above. The storage medium may be any medium capable ofstoring program codes, such as ROM, RAM, magnetic disk, or CD-ROM.

Finally, it should be noted that the embodiments of the presentinvention are intended for describing the technical solution of thepresent invention other than limiting the present invention. Althoughthe present invention is described in detail with reference to theforegoing embodiments, persons of ordinary skill in the art shouldunderstand that they can still make modifications to the technicalsolution described in the foregoing embodiments or make substitutions tosome technical features thereof, without departing from the spirit andscope of the technical solution of the embodiments of the presentinvention.

What is claimed is:
 1. A precoding processing method, comprising:selecting, by a user equipment (UE), a codebook vector for performingprecoding processing for data among a codebook set of N_(t) antennas,wherein the codebook set comprises a first codebook vector$\quad\begin{bmatrix}A \\B\end{bmatrix}$  and a second codebook vector $\quad\begin{bmatrix}A \\{- B}\end{bmatrix}$  generated according to the first codebook vector, A is a(N_(t)/2)×1 vector composed of a first half of elements of the firstcodebook vector, B is a (N_(t)/2)×1 vector composed of a last half ofelements of the first codebook vector, and N_(t) is a positive evennumber; and sending, by the UE, an index number of the codebook vectorto a base station; wherein: N_(t)=8, the codebook set comprises Kcodebooks where K is an integer, an 8×1 codebook vector$\quad\begin{bmatrix}A \\B\end{bmatrix}$  corresponding to K/2 codebooks in the K codebooks isrespectively obtained by using an 8-dimensional discrete Fouriertransformation codebook structure, and a number of discrete Fouriertransformation groups is K/(2N_(t)); the codebook vector of the otherK/2 codebooks in the K codebooks is $\quad{\begin{bmatrix}A \\{- B}\end{bmatrix},}$  where A is a vector composed of first 4 elements inthe 8×1 codebook vector, and B is a vector composed of last 4 elementsin the 8×1 codebook vector; and a codebook design of the first codebookvector $\quad\begin{bmatrix}A \\B\end{bmatrix}$  utilizes a discrete Fourier transformation codebookstructure; wherein the discrete Fourier transformation codebookstructure is as follows:${\mathbb{e}}_{m}^{(g)} = {\frac{1}{\sqrt{M}}\begin{bmatrix}w_{0m}^{(g)} & \ldots & w_{{({M - 1})}m}^{(g)}\end{bmatrix}}^{T}$$w_{nm}^{(g)} = {\exp\left\{ {j\;\frac{2\pi\; n}{M}\left( {m + \frac{g}{G}} \right)} \right\}}$where superscript T represents a transpose operation, M is a number ofdimensions of discrete Fourier transformation and M=8, with m=0, 1 . . .M−1 and n=0, 1 . . . M−1, G is the number of discrete Fouriertransformation groups, with g=0, 1, . . . , G−1, and e_(m) ^((g)) is aprecoding vector in the codebook set, and w_(nm) ^((g)) representselements in e_(m) ^((g)).
 2. The precoding processing method accordingto claim 1, wherein: the selecting, by the UE, the codebook vector forperforming precoding processing for the data among the codebook set ofN_(t) antennas comprises at least one of: selecting, by the UE, thecodebook vector in the first codebook vector and the second codebookvector of the codebook set if a configuration mode of the antennas is adual polarization configuration mode; and selecting, by the UE, thecodebook vector in the first codebook vector of the codebook set if theconfiguration mode of the antennas is a uniform linear arrayconfiguration mode.
 3. The precoding processing method according toclaim 1, wherein: the selecting, by the UE, the codebook vector forperforming precoding processing for the data among the codebook set ofN_(t) antennas comprises at least one of: selecting, by the UE, thecodebook vector in the first codebook vector and the second codebookvector of the codebook set if a configuration mode of the antennas is adual polarization configuration mode; and selecting, by the UE, thecodebook vector in the first codebook vector of the codebook set if theconfiguration mode of the antennas is a uniform linear arrayconfiguration mode.
 4. A user equipment, comprising: a codebookselecting module, configured to select a codebook vector for performingprecoding processing for data among a codebook set of N_(t) antennas,wherein the codebook set comprises a first codebook vector$\quad\begin{bmatrix}A \\B\end{bmatrix}$  and a second codebook vector $\quad\begin{bmatrix}A \\{- B}\end{bmatrix}$  generated according to the first codebook vector, and Ais a (N_(t)/2)+1 vector composed of a first half of elements of thefirst codebook vector, B is a (N_(t)/2)×1 vector composed of a last halfof elements of the first codebook vector, and N_(t) is a positive evennumber; a transmitter, configured to send an index number of thecodebook vector selected by the codebook selecting module to a basestation; and a first storage module, configured to store the codebookset, wherein N_(t)=8, and the codebook set comprises K codebooks where Kis an integer; wherein an 8×1 codebook vector $\quad\begin{bmatrix}A \\B\end{bmatrix}$  corresponding to K/2 codebooks in the K codebooks isrespectively obtained by using an 8-dimensional discrete Fouriertransformation codebook structure, a number of discrete Fouriertransformation groups is K/(2N_(t)), and a codebook vector of the otherK/2 codebooks in the K codebooks is $\quad{\begin{bmatrix}A \\{- B}\end{bmatrix};}$ wherein A is a vector composed of first 4 elements inthe 8×1 codebook vector, and B is a vector composed of last 4 elementsin the 8×1 codebook vector; and wherein the codebook selecting module isconfigured to select a codebook vector for performing precodingprocessing for data among the codebook set stored by the first storagemodule; wherein the codebook design of the first codebook vector$\quad\begin{bmatrix}A \\B\end{bmatrix}$  utilizes a discrete Fourier transformation codebookstructure; and wherein the discrete Fourier transformation codebookstructure is as follows:${\mathbb{e}}_{m}^{(g)} = {\frac{1}{\sqrt{M}}\begin{bmatrix}w_{0m}^{(g)} & \ldots & w_{{({M - 1})}m}^{(g)}\end{bmatrix}}^{T}$$w_{nm}^{(g)} = {\exp\left\{ {j\mspace{11mu}\frac{2\pi\; n}{M}\left( {m + \frac{g}{G}} \right)} \right\}}$where superscript T represents a transpose operation, M is a number ofdimensions of discrete Fourier transformation, M=8, with m=0, 1 . . .M−1 and n=0, 1 . . . M−1, G is the number of discrete Fouriertransformation groups, with q=0, 1, . . . , G−1. e_(m) ^((g)) is aPrecoding Vector in the Codebook Set, and w_(nm) ^((g)) Representselements in e_(m) ^((g)).
 5. The user equipment according to claim 4,wherein the codebook selecting module comprises: a judging unit,configured to judge whether a configuration mode of the antenna is adual polarization configuration mode or a uniform linear arrayconfiguration mode; and a selecting unit, configured to: select thecodebook vector in the first codebook vector and the second codebookvector of the codebook set if the judging unit determines that theconfiguration mode of the antenna is a dual polarization configurationmode; and select the codebook vector in the first codebook vector of thecodebook set if the judging unit determines that the configuration modeof the antenna is a uniform linear array configuration mode.
 6. The userequipment according to claim 4, wherein the codebook selecting modulecomprises: a judging unit, configured to judge whether a configurationmode of the antenna is a dual polarization configuration mode or auniform linear array configuration mode; and a selecting unit,configured to: select the codebook vector in the first codebook vectorand the second codebook vector of the codebook set if the judging unitdetermines that the configuration mode of the antenna is a dualpolarization configuration mode; and select the codebook vector in thefirst codebook vector of the codebook set if the judging unit determinesthat the configuration mode of the antenna is a uniform linear arrayconfiguration mode.